INSTRUCTING EXPERTS: FAILURE TO HAVE CLEAR IDENTIFICATION OF ISSUES COMPOUNDS THE PROBLEMS

In Astex Therapeutics Limited -v- Astranzenca AB [2017] EWHC 1442 (Ch) Mr Justice Arnold considered lengthy and complex issues in relation to compounds. However even in a case of such complexity the evidence of the experts should have been more limited. It is an example of experts being asked to report on factual issues and matters which were outside the scope of expert evidence in any event.

“The moral of the story, which is not a new one, is that what is required is clear identification of the issues which experts are going to be asked to address before the experts are instructed. Only if the issues are clearly identified is it possible to ascertain whether the experts can give evidence directed to those issues which is (a) admissible and (b) likely to be of sufficient weight for the cost of preparing their evidence to be proportionate to what is at stake.”

THE CASE

The parties were in dispute about whether certain pharmaceutical compounds were “Collaboration Compounds” within the terms of an agreement. Each side called an expert.

THE JUDGE’S COMMENTS ON THE EXPERT EVIDENCE

The expert witnesses

On 18 April 2016 Chief Master Marsh made an order for directions which gave each party permission to call one expert witness in the field of pharmaceutical drug discovery. As I understand it, that aspect of the order was made by consent. The order also provided for sequential service of experts’ reports, with (somewhat unusually) AstraZeneca’s expert’s report being served first. Perhaps partly as a result, AstraZeneca’s expert ended up serving three expert reports and Astex’s expert two. I am concerned that, through no fault of the experts, a considerable amount of money was wasted upon the preparation of these reports. I do not doubt that there was a role for expert evidence in this case, in particular to educate the court as to the technical background and to the general processes of drug discovery as at the date of the Agreement. But the parties do not appear clearly to have identified the issues which the experts should address in their reports prior to instructing their experts. Moreover, both sides instructed their expert to consider the history of the way in which CD1 and CD2 were developed as revealed by the witness statements and (at least to some extent) the contemporaneous documents. Given that neither expert professed expertise as a forensic investigator, such evidence was of doubtful admissibility. Astex’s expert was also instructed to set out his interpretation of particular clauses and phrases in the Agreement, evidence which was plainly inadmissible. Even if it was admissible, the cost of preparing this evidence will certainly have been disproportionate to its value in resolving the issues.

At the beginning of the trial I was presented with a proposed trial timetable which envisaged the experts giving oral evidence for a total of three days. As I pointed out, as if that was not bad enough, if the experts were to be cross-examined in detail about the history, they would not only need to read those contemporaneous documents which they had not already read, but also need either to sit through, or read the transcripts of, the oral evidence of many of the factual witnesses. The costs of these exercises would again be considerable, and disproportionate to their value in resolving the issues given that I was to have first-hand evidence from many of the key scientists involved in the development of CD1 and CD2. I therefore suggested that oral expert evidence be limited to, say, half a day each. AstraZeneca subsequently proposed that cross-examination of the experts be dispensed with. Astex did not accept that proposal, but did agree that the scope of the oral expert evidence should be limited to certain topics. Regrettably, I later discovered that this was not sufficient for the experts to be stood down from attending the entire trial. After the conclusion of the factual evidence and before the experts were called, I discussed with the parties the scope of cross-examination. Apart from directing that the oral evidence be limited to half a day each, I did not formally restrict the scope of cross-examination, but I did make it clear that I was unlikely to be assisted by cross-examination directed to some of the topics proposed. I am happy to record that both leading counsel completed their respective cross-examinations in less than the time allowed. Despite that, I am very concerned the overall cost of the expert evidence will have been grossly disproportionate.

The moral of the story, which is not a new one, is that what is required is clear identification of the issues which experts are going to be asked to address before the experts are instructed. Only if the issues are clearly identified is it possible to ascertain whether the experts can give evidence directed to those issues which is (a) admissible and (b) likely to be of sufficient weight for the cost of preparing their evidence to be proportionate to what is at stake.

WAS THE EXPERT EVIDENCE USEFUL?

Consider paragraph 45 of the judgment. We can only speculate as to the total cost of the expert evidence.

“This is not a case in which it is necessary for me to decide which of the two experts’ evidence I prefer, since in my view neither of them was in a position to give any evidence of real weight on the points which matter.”